Conventionally, a user usually uses a flight bag or hand bag to store a portable personal computer (e.g., lap top computer) to carry. But this is unsatisfactory for the purpose for which the invention is concerned for the following reason. No protective mechanism has been provided. As such, this portable personal computer may be damaged due to collision with the frame when the attache case is not in a horizontal position. To the worse, this portable personal computer may malfunction when the bag falls on the ground heavily. Thus, it is desirable to provide an improved attache case in order to overcome the above drawbacks of prior art.